561749731 has 8 divisors (see below), whose sum is σ = 568561104. Its totient is φ = 554977920.

The previous prime is 561749707. The next prime is 561749761. The reversal of 561749731 is 137947165.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 561749731 - 2⁷ = 561749603 is a prime.

It is a super-2 number, since 2×561749731² = 631125520557144722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (561749701) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19191 + ... + 38623.

It is an arithmetic number, because the mean of its divisors is an integer number (71070138).

Almost surely, 2^561749731 is an apocalyptic number.

561749731 is a deficient number, since it is larger than the sum of its proper divisors (6811373).

561749731 is a wasteful number, since it uses less digits than its factorization.

561749731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19781.

The product of its digits is 158760, while the sum is 43.

The square root of 561749731 is about 23701.2601141796. The cubic root of 561749731 is about 825.1146365342.

The spelling of 561749731 in words is "five hundred sixty-one million, seven hundred forty-nine thousand, seven hundred thirty-one".